B.1.2 N Complex Multiplies; B.1.3 Complex Correlation Or Convolution (Complex Fir) - Motorola DSP56800 Manual

B.1.2 N Complex Multiplies
; cr(I) + jci(I) = ( ar(I) + jai(I) ) * ( br(I) + jbi(I) ), I=1,...,N
; cr(I) = ar(I) * br(I) - ai(I) * bi(I)
; ci(I) = ar(I) * bi(I) + ai(I) * br(I)
opt cc
MOVE #AD,R0
MOVE #C-1,R2
MOVE #BD,R3
MOVE
DO #NUM,END_DO8
MOVE
MPY Y1,X0,A
MOVE
MPY Y0,X0,B
MACR -Y0,X0,A
MACR Y1,X0,B
END_DO8
MOVE B,X:(R2)+
;
;
B.1.3 Complex Correlation Or Convolution (Complex FIR)
; cr(n) + jci(n) = SUM(I=0,...,N-1)
; { ( ar(I) + jai(I) ) *
; cr(n) = SUM(I=0,...,N-1)
; { ar(I) * br(n-I) - ai(I) * bi(n-I) }
; ci(n) = SUM(I=0,...,N-1)
; { ar(I) * bi(n-I) + ai(I) * br(n-I) }
opt cc
MOVE #AD,R0
MOVE #BD,R3
CLR A
CLR B
DO #N,END_DOB
MAC Y0,Y1,A
MAC Y0,X0,B
MAC Y0,Y1,B
MAC -Y0,X0,A
MOVE
B-4
X:(R2),B
X:(R0)+,Y1
B,X:(R2)+
X:(R0)+,Y0
X:(R3)+,X0
A,X:(R2)+
( br(n-I) + jbi(n-I) ) }
X:(R0)+,Y0
X:(R3)+,Y1
X:(R3)+,X0
X:(R0)+,Y0
X:(R3)+,Y1
X:(R0)+,Y0
DSP56800 Family Manual
Y1=ar
Y0=ai X0=br, bi
; 2 2
; 2 2
; 2 2
;
; 2 3
X:(R3)+,X0 ; 1 1
; 1 1
;
; 1 1
; 1 1
;
; 1 1
; 1 1
; 1 1
_______
Total: 15 6N+11
Y0=ar Y1=br
Y0=ai X0=bi
; 2 2
; 2 2
; 1 1 ar
; 1 1 br
; 2 3
; 1 1 ar*br ,ai,bi
; 1 1 ar*bi
; 1 1 ar*bi+ai*br,ar
; 1 1 ar*br-ai*bi
; 1 1
dummy move!
get ar,br
ar*br,
store imag
get ai
ai*br, get bi
get bi
ar*br-ai*bi
ar*bi+ai*br,
store real